1. It is obvious that _______________________ (污染的空气) is harmful to our health. (pollute)
2. The wolf says ______________________________ (用令人恐怖的声音) that he is so hungry and he will eat Master Dongguo as the meal. (frighten)
3. ---What’s happening in the street?
---A group frequently ____________________ (自称) Green Peace are on parade in the sreet. (call)
